Numerous examples of fifth wheels may be found in the patent literature. Essentially the fifth wheel is a device which locks about a kingpin depending from a trailer and supports the forward end of the trailer for towing by a tractor. The fifth wheel may be tiltable about an axis transverse to the length of the trailer and may be mounted on a longitudinal slide on the tractor. However, no known fifth wheel assemblies are movable about a vertical axis; therefore there is a frictional interface between the deck plate of the fifth wheel and the undersurface of the trailer. Accordingly, this frictional interface can occasionally result in a resistance to turning which causes the wheels of the tractor to wear out more rapidly. Also associated with the connection of the tractor to the trailer is the use of what are called pigtails. Pigtails are the flexible connector units which connect the hydraulic, pneumatic or electrical systems of the tractor to the trailer. Current practice requires the operator to manually locate the pigtails and properly connect them. This requires the driver to get out of the tractor and perhaps climb onto the deck or beneath the trailer to locate the pigtails and make the connection. Conventional fifth wheel areas are quite greasy and considerable road grime accumulates in the area, thus securing the pigtails is a somewhat unpleasant task.